One of my earliest cooking memories is making jam from wild fruit that we had picked as a family. This was in the years before the ubiquitous “pick your own farms”. Instead we picked fruit that was growing free and wild near our home on land that no one seemed to own. Mostly it was blackberries which don’t make the best jam to be honest because the pips tend to get stuck in your teeth. You could avoid that by making blackberry jelly but the straining involved was quite a faff. Or you could you could add some apple to reduce the amount of pips and improve the flavour.
But my favourite was always raspberry jam. We could only get enough free raspberries to make this in a bumper year and provided that others hadn’t got to the raspberry bushes first. It was so nice to eat and a lot of the joy came from knowing that you had made it. I remember the big pot foaming and my mum teaching me about the need for a rolling boil and how to test for a set.
Here in Hong Kong, there are no local raspberries; the imported ones seem to be lacking in flavour and they’re a bit expensive for jam-making. Anyway, you can buy the definitive English raspberry jam in the shops here – Tiptree’s near-legendary ‘Sweet Tip’ Raspberry Conserve. You can’t really beat that so, without the economic incentive we had to make our own when I was a kid, there’s not much point in raspberry jam-making whilst you’re in Hong Kong.
But that opens up new opportunities for tropical fruit jam. Passion fruit is my favourite. They have a wonderful scented aroma nothing like any other fruit. They’re small and a little expensive and, although that aroma goes a long way, you really need something to bulk out the jam. Mango makes the ideal companion.
It turns out to be surprisingly hard to find passion fruit in Hong Kong. I’ve found the most reliable place to be the Graham Street market in Central. There are a few stalls between Gage Street and Queens Road that usually have a box or two of passion fruit. My economics training can’t fail to notice that there is a weird thing going on with the prices: the nearer the top of the hill, the more expensive they are. On my last visit: HK$7 for one near the top, by Gage Street, and HK$10 for four, nearest the bottom. I guess more people start at the top and, once they see what they want, they buy because they don’t want to walk all the way down and then have to climb back up to get them.
For ripe passion fruit, you want ones that are going wrinkly. Ironically, if you do see them in supermarkets, this is just when the supermarkets reduce the price so you may be able to get a bargain. Try to get relatively heavier ones for more flesh and avoid ones that are broken or badly mis-shaped
Mangoes are obviously more widely available. I would suggest buying larger ones because you need quite a volume and bigger ones are less hassle to skin and get the flesh from. For jam, you actually want slightly under-ripe fruit if anything because it contains more of the natural setting agent, pectin. You don’t really need the very best fruit for this so keep your expensive Alphonse mangos for another time.
You needn’t bother too much about pectin with the passion fruit – I think you want the maximum aroma and flavour from them which means using them when they are really ripe. If the passion fruit are still shiny and smooth, store them (not in the fridge) and they will ripen naturally in a few days.
The only other ingredients you need are some lemon juice and sugar. The lemon juice adds a little tartness which helps give a fresher taste. It also adds some further pectin.
For the sugar, you can use plain white granulated sugar which is fine. But you might want to look out for specialised jam sugar which has some pectin added. I’ve bought this sometimes from Wellcome or GREAT here in Hong Kong and it is worth using, especially if you are using fruit with a lowish pectin content like mango.
There are other tricks for adding natural pectin but, unless you plan on keeping your jam for months, you can ignore these. In the UK, we used to buy bottled pectin (Certo brand if I remember correctly) and in the US they sell pectin derived from apples for the same purpose. But I’ve never seen that or anything similar in Hong Kong so we’ll make do without.
There is another type of sugar called, confusingly, preserving sugar. This has no added pectin but has larger crystals which supposedly reduce the possibility of burning and the amount of impurities in the jam that rise to the surface as scum. But there are other ways of dealing with both those problems so it’s no big deal.
Too set in your ways?
Classic jam has a firm set. Some people like the flavour this gives and the way it spreads on bread. A good set gives you the best possible preserving effect so, if you are planning to keep the jams for months, this is the way to go. However some people think that the heat needed to get jam to this stage and the volume of sugar needed relative to the fruit makes for a less fresh tasting jam. If I understand the science involved, you need to boil the fruit and sugar mixture for long enough for moisture to evaporate leaving a concentration that is 65% sugar and it needs to reach a temperature of around 104C. That needs a quite a lot of sugar and quite a lot of boiling – hence those “rolling boils” I remember from my childhood.
So there is a bit of a trend for softer-set jams. At the extreme, these can be like a fruit compote. We are going to go for something in-between – less set than a traditional jam but still recognisably a jam-type spread. We are going to use a low sugar recipe which will produce a good consistency but it won’t get to the magic 104C setting point. The classic mix for a set jam is equal weights of sugar to fruit but we are going to go for only a quarter as much sugar as fruit although mangoes are themselves obviously very sweet and add a lot of natural sugar.
A sterile argument?
These jams are going to be hanging around for a few weeks at least though so we do need to sterilise the jars we will use to store them in. My mother used to use a rag-bag selection of jars that we had saved during the year for our summer and early autumn jam-making sessions. You’d find yourself eating blackberry and apple jam from a Branston pickle jar. Some of these jars were a bit iffy to be honest and we learned that, when we eventually opened the jar, there might be a layer of mould at the top which we would carefully remove before starting to scoff the jam below. That’s a bit frowned on nowadays although I can pronounce the immortal words: it never did me any harm. So we are going to use jars in good condition – it’s especially important that the tops still give a good seal. If you need to buy jars, there’s a variety of stuff out there in Hong Kong for preserving– Wing On has a several different types of jars in masses of different sizes for reasonable prices. I use the Italian jars seen in the photo above which have an ordinary screw top. And I don’t use wax covers or anything else. But I do sterilise these in an oven whilst the jam is cooking including the tops. I just put them on a large baking tray with the tops removed and at the side
More than a bit of a jam
The basic method is to steep the fruit and the sugar for a period and then heat at an increasing temperature. You’ll need to do this in large container. There are specialist jam making pans but the most easily available option is likely to be something like a large stockpot, preferably with a heavy bottom. You can do more or less than the quantities here according to your taste. If you’re new to jam-making, I would start with small quantities. Once it starts cooking, you need to keep stirring to avoid it burning on the bottom of the pot. A long wooden spatula is handy because it’s going to get hot.
Because we’re going for a soft-set, we are not going to bother too much about temperatures or testing for the set but just cook for a defined period of time.
I like the pips of the passion fruit which add a gentle crunch to the jam as well as a little visual interest. If you don’t like them, you can strain them out – ideally after the jam has made because the pips probably contain some extra pectin.
You’ll find a jam funnel useful for pouring or just about any funnel that has a reasonably wide neck that will fit in your jars. You want to fill the jars as close to the top as possible – less air means less possibility of spoilage. I seal the jars with their screw tops immediately and invert them for a few seconds – this means the still-hot jam does some sterilising on the top of the jar and the inside of the lid.
Remember in all this, you are dealing with a lot of hot sugary liquid which you don’t want to get on your skin, so be careful and use protective gloves.
- 2 kg mango flesh (about 8 large mangos) diced small
- 8 passion fruit
- 2 lemons - juice only
- 500g sugar – ideally jam sugar or white granulated sugar
- Mix together mango flesh and sugar and leave for 2 hours or overnight to infuse.
- Sterilise jars for 30 mins at 130C fan.
- Heat mango flesh and sugar over low heat for 5 mins to melt sugar, stirring.
- Add flesh of passion fruit.
- Raise heat to high heat for 20 mins stirring.
- Add lemon juice.
- If there is a lot of scum on the top of the jam, either remove it with a slotted spoon or add a knob of butter which will naturally disperse it.
- Decant the hot mixture into the sterilised jars almost to the top. Seal and briefly invert the jars to sterilise the tops. Take care with the hot liquid.